Lmao sorry. I agree with your overall point But this shit right here is so sig worthy. The Juubi was still gathering chakra since it was incomplete so it was nowhere near it's full strength plus the Juubi tail is entirely featless. That statement of yours makes absolutely no sense. Just because the Juubi in itself is stronger than the 9 tails doesn't mean it's tail is as strong.
Imo, feats even suggest otherwise. Hashirama used wood gates on his tails and the Juubi was completely immobilized. Kurotsuchi's father used a Rock technique which the Juubi with all his tails struggled to get out of.
:lol
It may not have been at full power, but it was still sending Kurama and Gyuki flying left and right, so that doesn't matter.
Juubi's tail is stronger than Bijuu tails as it was shown destroying mountains when in it's first form. And since when did a person's individual limbs act differently or have lower power levels than the rest of their body? Juubi's power = Juubi's tails' power.
Hashirama and Kurotsuchi's father managing to pull those stunts off isn't a determent to the Juubi's power, but a testament to their own power, much like Hiashi.
Hashirama is self-explanatory considering Orochimaru with Hashroids couldn't control him yet Kabuto did fine against a Rennigan Madara enhanced by Hashiroids. And Kurotsuchi's father needed a notable amount of time to build up the amount of Chaka to use that mountain technique, which he himself points out, and considering he is Kurotsuchi's father, him being that strong isn't far fetched.